Whites TDI Classroom

Some people think there is some magical difference between the TDI and the Pro, but there isn't . The truth is, both use the same motherboard and only differ by these three things. First, the Pro has a vernier GB control which is done by simply inserting another pot in one of the GB pot wires. Next, the internal volume control on the TDI is removed and a new pot is soldered to the motherboard in place of the removed volume pot used on the regular TDI. Finally, here is the real important difference and that is two capacitors are changed to different values.

The TDI has .22uf caps and the Pro has .10uf caps on the differential integrator stages. Now here is the beauty, change these two caps on the TDI and you have a "poor man's" TDI Pro. The vernier GB pot isn't needed here in the US nor is the volume control.

Owners who had The mods done to reduce the noise and had the "Pro" capacitor change mod already have this capacitor change and already do have an improved poor man's Pro. I say improved because they have the noise reduction mod that is already in the SL.

Actually, the TDI noise reduction mod it is an improved version of the SL mod that makes the SL threshold so quiet. Actually, SL's made from 2015 and later have the improved version also. In late 2014 a strange "hiccup" noise was causing serious concerns in Australia on a version of the SL called the SPP (Sierra Pulse Pro). With help of Alan Holcomb (then retiring CEO of Whites providing equipment and the assistance of Luke Lindsay who lives in Australia, we managed to solve the hiccup problem. This simple mod now installed in SL motherboards since late 2014 makes the later produced SL much easier to ground balance without hurting the noise reduction. (Earlier SL's could benefit from these "hiccup" mods also).

I mention this because there is a guy who just may be doing the TDI and SL mods in the future. I will mention more when the time is right. Hopefully, that will be soon.

Reg, You have been involved with the TDI from the beginning of its conception. I know you see the mods as an improvement to the unit ......but in the use of the first TDI did you feel the unit worked as a peak machine to find gold ? I have two original TDI machines now with no added mods and just want to keep them original as manufactured. What is your opinion?

Some great information,i own what was the last TDI pro that came into the UK before the battery transport problem stopped production,it due too come out of warranty at christmas time and although its a beast as it currently is,was wondering can the performance be pushed even further with some 'reliable' internal mods or not advisable ??

Many thanks

Deus and Nexus MP main everyday detectors

Displays on a Detector are really the equivalent of relying on sub-titles,give me a Analogue machine anyday.

QuoteMega
Some great information,i own what was the last TDI pro that came into the UK before the battery transport problem stopped production,it due too come out of warranty at christmas time and although its a beast as it currently is,was wondering can the performance be pushed even further with some 'reliable' internal mods or not advisable ??

Many thanks

In my opinion that would be a definite 'Not advisable'..

Happy Hunting
Minelab GPX-5000 - Backup GPX-4500 with a very large selection of coils.